"I have to get from one part of the world to the other, by doing so I have to transit through the South China Sea — what I can say is whatever I choose to do will be in full compliance with international law," Commander Canale told the ABC on board the Type 23 Frigate.

The commander is declining to say whether HMS Sutherland could sail within 12 nautical miles of a disputed territory or artificial island claimed by the Chinese, as US warships have done.

"It's very important that we demonstrate that these are seas ... anyone can pass through and we'll be making sure that the Royal Navy will protect those rights for international shipping as she goes to do joint operations with the Japanese, the Koreans and the United States Navy," Secretary Williamson told the ABC.

Bagpipes played on board the frigate docked in Sydney on Friday morning, after a ceremonial gun salute against the picturesque backdrop of the Sydney Harbour Bridge and Opera House.

Sydney is the final Australian stop for the crew, which has also visited Perth, Adelaide and Melbourne since departing Plymouth in January.

HMS Sutherland is an anti-submarine warship similar to the new Type 26 design the UK is hoping to build for Australia as part of the $35 billion Future Frigate Program, which is also being contested by Spanish and Italian shipbuilders.